So you want to buy a used laptop, #1First and formost do your reserch there are many places on the internet to check specifications and read reveiws on laptops, #2 Take your time and write down what you want to do with the machine,#3  make sure it has the specifications that will be above what your minimum requirements are, #4 Some computers are not woth doing upgrades or cannot be upgraded.This is where the reviews and specifics for the model come in, #5 You can also look for recalls on certain models.#6 Dont buy machines that are not complete and think you are going to get a deal and piece one together this usually ends up costing twice as much as a working machine would have.#7 If it doesnt work as soon as you get it contact the seller right away dont wait and by all means dont try to repair it  yourself,The seller in most cases will be helpfull and you can work it out with them as to the next move,#8Comunication is the key if your not sure ask,still not sure move on to another one that your sure on,#9 Warranty does seller offer a warranty,There are usually options for extended warrantys and in most cases its wise to purchase them.Laptops and PC'S are not cheap and if you break down the warranty into a yearly figure its alot less then what a new machine would cost you, I have Been A Computer Tech For years And Have Seen just About Everything And Anything,If you follow the steps and do a little reserch you will get the best machine for your money and have alot less headaches,And Alot more fun,So Have Fun Be Safe And Remember "Comunication,Reserch,and Reviews,Are What to Look For